The project deals with a continuation study of the effect of chronic administration of alcohol on the heart of dogs. Determinations of biochemical alterations in the heart muscle and the impact of these alterations on the contractility of the hearts of these animals are the principal objectives of this study. Of interest are mitochondrial changes as they influence respiratory reserve. The effect of these biochemical changes on the mechanial functions of the heart will be studied by investigating the relationship between respiratory reserve in mitochondria and cardiac function during stress. Studies will be continued in order to demonstrate disturbances in other mitochondrial functions in these hearts. They include, in addition to respiratory reserve, intramitochondrial and extramitochondrial enzymes.